Modular parallel technique for resonant converter

Abstract

An LLC resonant converter includes a first phase with a first primary circuit and a second phase with a second primary circuit. The first primary circuit includes a first shared inductor, and the second primary circuit includes a second shared inductor. The first and second shared inductors are connected in parallel with each other. The first and second primary circuits do not include a capacitor that is connected in parallel with each other.

What is claimed is: 
     
       1. An LLC resonant converter comprising:
 a voltage input; 
 a voltage output; 
 a first phase including:
 a first transformer with first primary and first secondary windings; 
 a first primary circuit connected to the voltage input and the first primary winding, the first primary circuit including:
 a first resonant capacitor; 
 a first magnetizing inductor connected in parallel across the first primary winding; and 
 a first resonant inductor; wherein 
 the first resonant capacitor, the first magnetizing inductor, and the first resonant inductor are connected in series; 
 
 a first secondary circuit connected to the first secondary winding and the voltage output, the first secondary circuit including a first rectifying circuit; and 
 a second phase including: 
 a second transformer with second primary and second secondary windings; 
 a second primary circuit connected to the voltage input and the second primary winding, the second primary circuit including:
 a second resonant capacitor; 
 a second magnetizing inductor connected in parallel across the second primary winding; and 
 a second resonant inductor; wherein 
 the second resonant capacitor, the second magnetizing inductor, and the second resonant inductor are connected in series; 
 
 a second secondary circuit connected to the second secondary winding and the voltage output, the second secondary circuit including a second rectifying circuit; wherein 
 
 the first primary circuit includes a first shared inductor with first and second ends; 
 the second primary circuit includes a second shared inductor with first and second ends; 
 the first and second shared inductors are connected in parallel with each other such that the first ends of the first and second shared inductors are directly connected to each other, and the second ends of the first and second shared inductors are directly connected to each other; and 
 the first and second primary circuits do not include a capacitor that is connected in parallel with each other. 
 
     
     
       2. The LLC resonant converter of  claim 1 , wherein the first and second rectifying circuits include synchronous rectifiers. 
     
     
       3. The LLC resonant converter of  claim 1 , wherein the first phase includes a first output capacitor, and the second phase includes a second output capacitor. 
     
     
       4. The LLC resonant converter of  claim 1 , further comprising at least one additional phase including at least one additional shared inductor; wherein
 the at least one additional shared inductor is connected in parallel with the first and second shared inductors. 
 
     
     
       5. The LLC resonant converter of  claim 1 , wherein:
 the first shared inductor is the first resonant inductor; and 
 the second shared inductor is the second resonant inductor.